Gallery
At the north-eastern end of the gallery is a well-preserved example of the pavilion vaults which originally made up the roof, almost completely hidden by later alterations. On the wall, a large fragment of a marble lintel from the Temple of Concordia in the Roman Forum dating back to the I century AD.
The large archways in the gallery were walled up during the Middle Ages as part of the building's transformation into a fort, and have only been partially restored. They afford an excellent view over the whole archaeological area of the Roman Forum, with the Colosseum and Palatine Hill in the background.
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In front of the Roman Forum, the large arches of the arcade in opus quadratum made of gabine stone (a kind of tufa coming from the territory of ancient Gabii), as a great bridge, put in communication the two sides of the hill. It consists of 11 spans, originally covered by a cloister vault, supported by gabine stone columns with capitals and cornices in travertine; the last span preserves the original vault.
The gallery overlooked five blind rooms, which were similar and parallel.
A steep staircase, inside the substructio and no longer accessible, connects the floor of the Roman Forum to the Temple Vejovis; a second ramp, opposite to the first and preserved only in part, connected to the upper floors of the Tabularium and probably to the archive.
A plate glass, at the centre of the corridor, closed the ventilation shaft of a water culvert built in the lower gallery during the Flavian period.